Technical Field
The invention describes an injection device consisting of an injector and an ampoule unit for the needle-free injection of a medium.
Description of the Related Art
The document DE 699 28 012 T2 describes an injection device, DE 101 37 961 A1 relates to an ampoule for an injection device, DE 201 05 183 U1 relates to an ampoule for a needle-free injection device, EP 1 762 261 B1 discloses a device for the administration of an injectable product, and EP 0 114 145 A2 describes a syringe for medical use. WO 2007/065544 and WO 2007/065542 disclose injection devices.
These documents disclose an injection device for the needle-free injection of a medium, with an injector and an ampoule unit, where the ampoule unit has a basic body which is intended to hold the medium for injection. FIG. 1 shows in detail essentially the embodiment according to the prior art.
FIG. 1 shows in cross section an ampoule unit according to WO 2007/065544. The embodiment shows the structural design of the ampoule unit 1. The latter consists of a basic body 4 which is filled with the medium 3, and which is completely enclosed in the longitudinal direction by a sleeve. At the front end, a nozzle 13 (preferably a steel nozzle) is located which is fixed mechanically in a way that provides a seal for the medium to the basic body 4 or the sleeve 5 via a sealing element 15 (preferably made of silicone), with friction and positive lock by means of a nozzle threading 19. At the outlet of the steel nozzle 13, a cap 14 is screwed on, where a cap seal 20 (made of a sterile material) is located again between the inner wall of the cap 14 and the outlet of the steel nozzle 13.
Before the injection, an ampoule unit as represented in FIG. 1 is screwed on, to apply the medium 3 (or inject it under the skin) after the removal of the cap 14 and of the cap seal 20, after the unit is placed on a certain area of the skin.